Failure of Gasoline Engine Control system components (sensors, ECM, injector, etcl) may result in interruption to the fuel supply or failure to supply the proper amount of fuel for various engine operating conditions. The following situations may be encountered:
Engine is hard to start or does not start at all.
Unstable idle.
Poor driveability
If any of the above conditions occurs, first perform a routine diagnosis including basic engine checks (ignition system malfunction, incorrectengine adjustment, etc.). Then, inspect the Gasoline Engine Control system components with the GDS.
Before removing or installing any part, read the diagnostic trouble codes and then disconnect the battery negative (-) terminal.
Before disconnecting the cable from battery terminal, turn the ignition switch to OFF. Removal or connection of the battery cable during engine operation or while the ignition switch is ON could cause damage to the ECM.
The control harnesses between the ECM and heated oxygen sensor are shielded with the shielded ground wires to the body in order to prevent the influence of ignition noises and radio interference. When the shielded wire is faulty, the control harness must be replaced.
When checking the generator for the charging state, do not disconnect the battery '+' terminal as doing so may damage the ECM due to voltage.
When charging the battery with the external charger, disconnect the vehicle side battery terminals to prevent damaging the ECM.
[EOBD]
The malfunction indicator lamp illuminates to notify the driver that there is a problem with the vehicle. However, the MIL will turn off automatically after 3 subsequent sequential driving cycles without the same malfunction. Immediately after the ignition switch is turned on (ON position without starting), the MIL will illuminate continuously to indicate that the MIL operates properly.
Faults with the following items will illuminate the MIL.
Catalyst
Fuel system
Manifold Absolute Pressure Sensor (MAPS)
Intake air temperature sensor
Engine coolant temperature sensor
ETC module (TPS & ETC motor)
Heated oxygen sensor (Upstream)
Heated oxygen sensor heater (Upstream)
Heated oxygen sensor (Downstream)
Heated oxygen sensor heater (Downstream)
Injector
Misfire
Crankshaft position sensor
Camshaft position sensor
Evaporative emission control system
Vehicle speed sensor
Power supply
ECM/ PCM
MT encoding
Acceleration sensor
MIL-ON request signal
Power stage
Refer to "Inspection Chart For Diagnostic Trouble Codes (DTC)" for more information.
[NON-EOBD]
The malfunction indicator lamp illuminates to notify the driver that there is a problem with the vehicle. However, the MIL will turn off automatically after 3 subsequent sequential driving cycles without the same malfunction. Immediately after the ignition switch is turned on (ON position without starting), the MIL will illuminate continuously to indicate that the MIL operates properly.
Faults with the following items will illuminate the MIL
Heated oxygen sensor (HO2S)
Manifold Absolute Pressure Sensor (MAPS)
Engine coolant temperature sensor (ECTS)
ETC module (TPS & ETC motor)
Injectors
ECM
Refer to "Inspection Chart For Diagnostic Trouble Codes (DTC)" for more information.
[Inspection]
After turning ON the ignition key, ensure that the light illuminates for about 5 seconds and then goes out.
If the light does not illuminate, check for an open circuit in the harness, a blown fuse or a blown bulb.
The ECM monitors the input/output signals (some signals at all times and the others under specified conditions). When the ECM detects an irregularity, it records the diagnostic trouble code, and outputs the signal to the Data Link connector. The diagnosis results can be read with the MIL or the GDS. Diagnostic Trouble Codes (DTC) will remain in the ECM as long as battery power is maintained. The diagnostic trouble codes will, however, be erased when the battery terminal or ECM connector is disconnected, or by the GDS.
If a sensor connector is disconnected with the ignition switch turned on, the diagnostic trouble code (DTC) will be recorded. In this case, disconnect the battery negative terminal (-) for 15 seconds or more until the diagnostic memory is erased.
When the same malfunction is detected and maintained during two consecutive driving cycles, the MIL will automatically illuminate.
The MIL will go out automatically if no fault is detected for 3 consecutive driving cycles.
A Diagnostic Trouble Code(DTC) is recorded in ECM memory when a malfunction is detected during two consecutive driving cycles. The MIL will illuminate when the malfunction is detected on the second driving cycle.
If a misfire is detected, a DTC will be recorded, and the MIL will illuminate, immediately after a fault is first detected.
A Diagnostic Trouble Code(DTC) will automatically be erased from ECM memory if the same malfunction is not detected for 40 driving cycles.
A "warm-up cycle" means sufficient vehicle operation such that the coolant temperature has risen by at least 40℉ from engine starting and reached a minimum temperature of 160℉.
A "driving cycle" consists of engine startup, vehicle operation beyond the beginning of closed loop operation.
